This invention relates to an ion exchange water treatment system of the type in which two or more ion exchangers are connected in parallel in a water system so as to provide relatively large treatment capacity while keeping water service available to the using system when one of the exchangers is in its regeneration cycle.
More particularly, the invention relates to an ion exchange water treatment system of the type in which a sensor is associated with each exchanger and detects when the exchanger needs regenerating. As an incident to such detection, the sensor causes the associated exchanger to begin a regeneration cycle.